1 /* 2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README 3 */ 4 5 #include <linux/capability.h> 6 #include <linux/fs.h> 7 #include <linux/mount.h> 8 #include "reiserfs.h" 9 #include <linux/time.h> 10 #include <linux/uaccess.h> 11 #include <linux/pagemap.h> 12 #include <linux/compat.h> 13 14 /* 15 * reiserfs_ioctl - handler for ioctl for inode 16 * supported commands: 17 * 1) REISERFS_IOC_UNPACK - try to unpack tail from direct item into indirect 18 * and prevent packing file (argument arg has t 19 * be non-zero) 20 * 2) REISERFS_IOC_[GS]ETFLAGS, REISERFS_IOC_[GS]ETVERSION 21 * 3) That's all for a while ... 22 */ 23 long reiserfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 24 { 25 struct inode *inode = file_inode(filp); 26 unsigned int flags; 27 int err = 0; 28 29 reiserfs_write_lock(inode->i_sb); 30 31 switch (cmd) { 32 case REISERFS_IOC_UNPACK: 33 if (S_ISREG(inode->i_mode)) { 34 if (arg) 35 err = reiserfs_unpack(inode, filp); 36 } else 37 err = -ENOTTY; 38 break; 39 /* 40 * following two cases are taken from fs/ext2/ioctl.c by Remy 41 * Card (card@masi.ibp.fr) 42 */ 43 case REISERFS_IOC_GETFLAGS: 44 if (!reiserfs_attrs(inode->i_sb)) { 45 err = -ENOTTY; 46 break; 47 } 48 49 flags = REISERFS_I(inode)->i_attrs; 50 err = put_user(flags, (int __user *)arg); 51 break; 52 case REISERFS_IOC_SETFLAGS:{ 53 if (!reiserfs_attrs(inode->i_sb)) { 54 err = -ENOTTY; 55 break; 56 } 57 58 err = mnt_want_write_file(filp); 59 if (err) 60 break; 61 62 if (!inode_owner_or_capable(inode)) { 63 err = -EPERM; 64 goto setflags_out; 65 } 66 if (get_user(flags, (int __user *)arg)) { 67 err = -EFAULT; 68 goto setflags_out; 69 } 70 /* 71 * Is it quota file? Do not allow user to mess with it 72 */ 73 if (IS_NOQUOTA(inode)) { 74 err = -EPERM; 75 goto setflags_out; 76 } 77 if (((flags ^ REISERFS_I(inode)-> 78 i_attrs) & (REISERFS_IMMUTABLE_FL | 79 REISERFS_APPEND_FL)) 80 && !capable(CAP_LINUX_IMMUTABLE)) { 81 err = -EPERM; 82 goto setflags_out; 83 } 84 if ((flags & REISERFS_NOTAIL_FL) && 85 S_ISREG(inode->i_mode)) { 86 int result; 87 88 result = reiserfs_unpack(inode, filp); 89 if (result) { 90 err = result; 91 goto setflags_out; 92 } 93 } 94 sd_attrs_to_i_attrs(flags, inode); 95 REISERFS_I(inode)->i_attrs = flags; 96 inode->i_ctime = current_time(inode); 97 mark_inode_dirty(inode); 98 setflags_out: 99 mnt_drop_write_file(filp); 100 break; 101 } 102 case REISERFS_IOC_GETVERSION: 103 err = put_user(inode->i_generation, (int __user *)arg); 104 break; 105 case REISERFS_IOC_SETVERSION: 106 if (!inode_owner_or_capable(inode)) { 107 err = -EPERM; 108 break; 109 } 110 err = mnt_want_write_file(filp); 111 if (err) 112 break; 113 if (get_user(inode->i_generation, (int __user *)arg)) { 114 err = -EFAULT; 115 goto setversion_out; 116 } 117 inode->i_ctime = current_time(inode); 118 mark_inode_dirty(inode); 119 setversion_out: 120 mnt_drop_write_file(filp); 121 break; 122 default: 123 err = -ENOTTY; 124 } 125 126 reiserfs_write_unlock(inode->i_sb); 127 128 return err; 129 } 130 131 #ifdef CONFIG_COMPAT 132 long reiserfs_compat_ioctl(struct file *file, unsigned int cmd, 133 unsigned long arg) 134 { 135 /* 136 * These are just misnamed, they actually 137 * get/put from/to user an int 138 */ 139 switch (cmd) { 140 case REISERFS_IOC32_UNPACK: 141 cmd = REISERFS_IOC_UNPACK; 142 break; 143 case REISERFS_IOC32_GETFLAGS: 144 cmd = REISERFS_IOC_GETFLAGS; 145 break; 146 case REISERFS_IOC32_SETFLAGS: 147 cmd = REISERFS_IOC_SETFLAGS; 148 break; 149 case REISERFS_IOC32_GETVERSION: 150 cmd = REISERFS_IOC_GETVERSION; 151 break; 152 case REISERFS_IOC32_SETVERSION: 153 cmd = REISERFS_IOC_SETVERSION; 154 break; 155 default: 156 return -ENOIOCTLCMD; 157 } 158 159 return reiserfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); 160 } 161 #endif 162 163 int reiserfs_commit_write(struct file *f, struct page *page, 164 unsigned from, unsigned to); 165 /* 166 * reiserfs_unpack 167 * Function try to convert tail from direct item into indirect. 168 * It set up nopack attribute in the REISERFS_I(inode)->nopack 169 */ 170 int reiserfs_unpack(struct inode *inode, struct file *filp) 171 { 172 int retval = 0; 173 int index; 174 struct page *page; 175 struct address_space *mapping; 176 unsigned long write_from; 177 unsigned long blocksize = inode->i_sb->s_blocksize; 178 179 if (inode->i_size == 0) { 180 REISERFS_I(inode)->i_flags |= i_nopack_mask; 181 return 0; 182 } 183 /* ioctl already done */ 184 if (REISERFS_I(inode)->i_flags & i_nopack_mask) { 185 return 0; 186 } 187 188 /* we need to make sure nobody is changing the file size beneath us */ 189 { 190 int depth = reiserfs_write_unlock_nested(inode->i_sb); 191 inode_lock(inode); 192 reiserfs_write_lock_nested(inode->i_sb, depth); 193 } 194 195 reiserfs_write_lock(inode->i_sb); 196 197 write_from = inode->i_size & (blocksize - 1); 198 /* if we are on a block boundary, we are already unpacked. */ 199 if (write_from == 0) { 200 REISERFS_I(inode)->i_flags |= i_nopack_mask; 201 goto out; 202 } 203 204 /* 205 * we unpack by finding the page with the tail, and calling 206 * __reiserfs_write_begin on that page. This will force a 207 * reiserfs_get_block to unpack the tail for us. 208 */ 209 index = inode->i_size >> PAGE_SHIFT; 210 mapping = inode->i_mapping; 211 page = grab_cache_page(mapping, index); 212 retval = -ENOMEM; 213 if (!page) { 214 goto out; 215 } 216 retval = __reiserfs_write_begin(page, write_from, 0); 217 if (retval) 218 goto out_unlock; 219 220 /* conversion can change page contents, must flush */ 221 flush_dcache_page(page); 222 retval = reiserfs_commit_write(NULL, page, write_from, write_from); 223 REISERFS_I(inode)->i_flags |= i_nopack_mask; 224 225 out_unlock: 226 unlock_page(page); 227 put_page(page); 228 229 out: 230 inode_unlock(inode); 231 reiserfs_write_unlock(inode->i_sb); 232 return retval; 233 } 234